Collection, storage and management of high-water marks data: praxis and recommendations

Abstract

High-water marks data, in its most general definition, is a precious source of information for the many stakeholders involved in risk culture, inundation mapping, river, estuarine or coastal studies, etc. Although there have already been many initiatives to collect and exploit existing data, as well as collecting new marks after flood events, a lack of harmonization and coordination remains. The French flood forecasting services, together with Cerema, decided to provide technical and organizational solutions in order to set up a collaborative management approach of high-water marks data. On the one hand, a methodological handbook has been produced, giving recommendations for post-flood field investigations. It comes with a dedicated PDA tool and a PC desktop software. On the other hand, a national repository has been built, making it possible to gather the large range of informations usually needed. This repository is combined with a collaborative web platform, which aims to be a way of public access to the available information, a working tool for technical users, and a front door to contribute to the inventory. The last step of this approach is the setting of an organization blue-print including all the stakeholders directly or indirectly involved in high-water marks knowledge.